Retroviral analysis reveals the ancient origin of Kihnu native sheep in Estonia: implications for breed conservation
Open Access
- 15 October 2020
- journal article
- research article
- Published by Springer Science and Business Media LLC in Scientific Reports
- Vol. 10 (1), 1-8
- https://doi.org/10.1038/s41598-020-74415-z
Abstract
Native animal breeds constitute an invaluable pool of genetic resources in a changing environment. Discovering native breeds and safeguarding their genetic diversity through specific conservation programs is therefore of high importance. Endogenous retroviruses have proved to be a reliable genetic marker for studying the demographic history of sheep (Ovis aries). Previous research has revealed two migratory episodes of domesticated sheep from the Middle East to Europe. The first episode included predominantly ‘primitive populations’, while the second and most recent is hypothesised to have included sheep with markedly improved wool production. To examine whether the recently discovered Kihnu native sheep in Estonia have historically been part of the first migratory episode and to what extent they have preserved primitive genetic characters, we analysed retroviral insertions in 80 modern Kihnu sheep and 83 ancient sheep from the Bronze Age to Modern Period (850 BCE–1950 CE). We identified that the Kihnu sheep have preserved ‘primitive’, ‘Nordic’, and other ‘ancient’ retrotypes that were present both in archaeological and modern samples, confirming their shared ancestry and suggesting that contemporary Kihnu native sheep originate from the first migratory episode. However, over the course of history, there has been a gradual decrease in the frequency of primitive retrotypes. Furthermore, Kihnu sheep possessed several ‘novel’ retrotypes that were absent in archaeological individuals, but were shared with improvement breeds, suggesting recent crossing within the last two centuries. To preserve these ancient lineages, our results are being applied in the conservation program of the Kihnu Native Sheep Society.Funding Information
- Horizon 2020 (749226, 747424)
- Eesti Teadusagentuur (PRG29)
- Academy of Finland (SA286499)
- Tartu Ülikool (PLTOM20905)
- European Research Council (787282)
This publication has 18 references indexed in Scilit:
- Old origin of a protective endogenous retrovirus (enJSRV) in the Ovis genusHeredity, 2018
- Three Thousand Years of Continuity in the Maternal Lineages of Ancient Sheep (Ovis aries) in EstoniaPLOS ONE, 2016
- Maternal and paternal genetic diversity of ancient sheep in Estonia from the Late Bronze Age to the post‐medieval period and comparison with other regions in EurasiaAnimal Genetics, 2016
- Evolutionary dynamics of endogenous Jaagsiekte sheep retroviruses proliferation in the domestic sheep, mouflon and Pyrenean chamoisHeredity, 2014
- Endogenous Retroviruses of Sheep: A Model System for Understanding Physiological Adaptation to an Evolving Ruminant GenomeThe Journal of Reproduction and Development, 2012
- Revealing the History of Sheep Domestication Using Retrovirus IntegrationsScience, 2009
- Endogenous retrovirusesCellular and Molecular Life Sciences, 2008
- A Paradigm for Virus–Host Coevolution: Sequential Counter-Adaptations between Endogenous and Exogenous RetrovirusesPLoS Pathogens, 2007
- Native breeds demonstrate high contributions to the molecular variation in northern European sheepMolecular Ecology, 2005
- Unfolding of population structure in Baltic sheep breeds using microsatellite analysisHeredity, 2005